This was easily our favorite stay in all of Greece. The home itself is a cave with two bedrooms and two bathrooms, though just myself and my wife stayed. The bed was comfy and the home contains a full kitchen. The pool is not heated, and was a little too cold for us to use in May.
We were welcomed by Nayia and Dani, who were very communicative via whatsapp and assisted with everything we needed, including setting up excursions. They were extremely hospitable beyond what you would expect from even a 5* hotel. We received delicious Greek breakfast every morning consisting of pastries and spreads, Juice, and yogurt, delivered straight to our door. We could plan exactly when we wanted breakfast, and when we wanted room service.
We especially loved the location. It is about a 20 minute walk from Oia, which I consider to easily be the best town on the island. This property connects directly to the hiking trail between Fira and Oia, which is breathtaking. My wife and I loved taking the hike every day, and relaxing by the cliff top church which had the best view of the caldera of the entire island. That said, if you do not enjoy walking this may not be the best place for you unless you are willing to rent a car/atv or pay for shuttles. The tradeoff here is that the property is much more private and secluded than the mashed together hotels in Oia.
We plan on staying here again if we come back to Santorini.